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Title: Comprehensive Evaluation for Protective Coatings: Optical, Electrical, Photoelectrochemical, and Spectroscopic Characterizations

Journal Article · · Frontiers in Energy Research

Numerous efficient semiconductors suffer from instability in aqueous electrolytes. Strategies utilizing protective coatings have thus been developed to protect these photoabsorbers against corrosion while synergistically improving charge separation and reaction kinetics. Recently, various photoelectrochemical (PEC) protective coatings have been reported with suitable electronic properties to ensure low charge transport loss and reveal the fundamental photoabsorber efficiency. However, protocols for studying the critical figures of merit for protective coatings have yet to be established. For this reason, we propose four criteria for evaluating the performance of a protective coating for PEC water-splitting: stability, conductivity, optical transparency, and energetic matching. We then propose a flow chart that summarizes the recommended testing protocols for quantifying these four performance metrics. In particular, we lay out the stepwise testing protocols to evaluate the energetics matching at a semiconductor/coating/(catalyst)/liquid interface. Finally, we provide an outlook for the future benchmarking needs for coatings.

Research Organization:
Yale University, New Haven, CT (United States)
Sponsoring Organization:
Japan Student Services Organization; National Science Foundation (NSF); USDOE; USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Grant/Contract Number:
EE0008092
OSTI ID:
1839483
Journal Information:
Frontiers in Energy Research, Journal Name: Frontiers in Energy Research Vol. 9; ISSN 2296-598X
Publisher:
Frontiers Media SACopyright Statement
Country of Publication:
Switzerland
Language:
English

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